Currently, typical concrete ventilating blocks are formed with straight, internal passages extending vertically through the block, such that when plural blocks are stacked, a ventilating “chimney” is formed. These and other block constructions are well represented in the patent literature. For example, U.S. Pat. No. 2,137,153 discloses ventilated wall blocks that are stacked vertically in an alternately inverted orientation, establishing both vertical and horizontal vent passageways. In U.S. Pat. No. 7,096,634, a block is disclosed that, when stacked, creates vertical vents or cores. Still other block constructions are disclosed in U.S. Pat. Nos. 1,758,757; 2,624,193; and 4,823,530. There remains a need, however, for a horizontally-vented block for use in wall constructions that allows horizontal air circulation through the wall, but that inhibits rain from passing through the wall and that also enhances the privacy of persons on the interior side of the wall.